Hair oil is a hair cosmetic that is used to supplement oil components in the hair and give it gloss, smoothness, and flexibility. As for the constituent ingredients, the main ingredient is plant oils (Camellia seed oil, olive oil, etc.) and/or mineral oil (liquid paraffin) having a low viscosity, to which higher fatty acid esters, squalane, silicone oils, etc. are added (Non-Patent Document 1).
For example, Patent Document 1 discloses a hair cosmetic containing a highly polymerized silicone that is superior in spreadability, smoothness, and tactile softness at the time of application on the hair and, after application on the hair, gives a smooth tactile sensation, softness, and appropriate sense of togetherness. Said hair cosmetic contains, as the constituent ingredients, a specific highly polymerized silicone, a volatile hydrocarbon oil, a cholesterol derivative, and a low-viscosity silicone oil. A non-water system is preferable, but, depending on the configuration and/or formulation form, a small amount of water and/or lower alcohol (ethanol) may be contained. However, the hair cosmetic described in Patent Document 1 does not contain the (b) ingredient of the present invention as a constituent ingredient and therefore the sensation during use is not necessarily as good as that of the invention of the present application.
Patent Document 2 is an invention by the applicant of the present application and it discloses hair cosmetics such as hair oil that give superior gloss and a smooth tactile sensation to the hair and also achieves opposing sensations during use, i.e. moist and loose tactile sensations. This hair cosmetic characteristically contains as constituent ingredients (A) 1-15 wt % of plant oils, (B) a volatile oil component, (C) a high molecular weight dimethylpolysiloxane, and (D) a dimethylpolysiloxane containing hydroxyl groups, polyoxyethylene groups and/or polyoxypropylene groups.
However, the hair oil described in Patent Document 2 does not contain ethanol, which is an essential ingredient in the invention of the present application, and therefore its sensation during use is worse than the invention of the present application. Furthermore, when the (b) ingredient of the invention of the present application is added to the invention described in Patent Document 2, the stability over time may deteriorate.